As the population and number of automobiles increase, the problem of the drunk driver and the effect of his driving on innocent victims will intensity. By 1975 it is estimated that 225,000,000 Americans will ride in 113,642,000 motor vehicles with 80 percent of both of these in the crowded metropolitan areas. Controlling drunk driving will, at that time, be imperative.
While various proposals and devices have been made in the past to deal with detection and control of the inebriate, these have suffered from several drawbacks. Chemical testing devices tend to be inconvenient, difficult and sometimes dangerous for use by any but a well-trained technician. These devices also tend to be prohibitively expensive to be placed in the ordinary passenger automobile. Most of these devices allow for avoidance of an accurate test except in the case of direct and alert supervision. For example, breath tests to be accurate require a deep lung breath sample and can be evaded by inhaling and exhaling repetitively so as to test only oral or mixed breath. Other testers (such as that shown in U.S. Pat. No. 3,311,187), which involve agility, memory, eyesight and/or reaction-time testing do not test alcoholic intoxication as legally defined and allow for errors of inclusion and exclusion.
The term "gas," as used herein and in the appended claims, embraces both ordinary air in the atmosphere, and breath exhaled from the lungs of a human subject.
"Vehicle," as used herein and in the claims, means any human-guided self-propelled unit, such as an automobile, train, airplane, motorboat, on-and off-the road unit, such as a snowmobile or bulldozer, and the like.